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Groundwater Monitoring Well MW-3 will be destroyed using a CME 75 drilling rig equipped with 12-inch-diameter, hollow-stem augers by drilling to the total depth of the well construction materials, and rotating sufficiently to bring to the surface as much of the well construction materials as practical. Due to the close proximity of property lines and the underground storage tank complex, the 4-inch-diameter recovery well will be installed in the borehole created during the destruction of MW-3. After redrilling Monitoring Well MW-3 to a depth of 10 to 15 feet (approximately 20 feet in total depth) below the top of the first saturated zone, the borehole will be converted into a recovery well using 4-inch-diameter, Schedule 40, PVC pipe, with the appropriate perforations and filter pack. A bentonite spacer will be installed above the sand pack, and the remainder of the annulus will be sealed with Portland Type I/II neat cement. The top of the well will be secured with water tight locking caps and utility boxes finished flush with the ground surface. Task 3: Develop and Survey the Recovery Well Well development will be performed to consolidate and stabilize the filter pack to optimize well production and reduce the turbidity of subsequent groundwater extracted. The well will be developed on the day of drilling before installation of the bentonite spacer and neat cement seal. Well development will be accomplished by alternately using a surge block and submersible pump or bailer to evacuate the water and sediment. Development will continue to a maximum of 10 saturated well volumes or until the groundwater is relatively free of sediments. The recovery well will be surveyed from the top of the casing to 0.01 foot accuracy in reference to an established benchmark or a common datum. Task 4: Connect New Recovery Well To Existing Treatment_System The existing submersible pump in MW-5 will be transferred to the new recovery well and connected to the existing discharge line between MW-3 and the treatment system. This will include electrical connection and necessary plumbing. Well production will be monitored to determine proper control settings. Task 5: Submit Well Construction Data Well construction data will be presented in the operation and maintenance report following installation and connection of the recovery well. E.\0\10-085\10-085.WP/161493 2